1. Field of the Invention
This invention relates to railing systems and, more particularly, to extruded aluminum railing systems and components thereof for use in crowd control, stairwells, office furniture restaurant equipment and the like.
2. Brief Description of the Prior Art
For years posts and ropes have been used for directing and containing crowds in restaurants, banks etc. The posts are square or cylindrical with the standard end caps being balls or flat caps. Only a very limited number of decorative end caps are on the market, i.e. horse head or acorn. While it is apparent that it would be desirable to have a universal structure which could interchangeably be used in essentially unrelated applications, the prior art devices have failed to achieve the desired end result.
In U.S. Pat. No. 4,014,520, Walters discloses a rail assembly system which departs from the common used systems. In the patent is disclosed a locking mechanism, as illustrated in FIG. 16, in which a U-shaped capping member 100 is provided with stepped serations 102a which embed themselves in the angular ridges 91a on the inside wall of the element 90 when the wedge 108 is forced downwardly and the two walls 102 are driven apart. FIGS. 2 and 18 to 20 disclose top channel elements which can be used with the Walters rail system. One of the problems encountered with this type of element locking system is that when used with anodized aluminum, the pressure generated by the interlocking of parts results in sufficient metal distortion to produce a undesirable blemish on the surface of the rail.
In U.S. Pat. No. 3,918,686 to Knott et al, a railing system is disclosed which includes pickets 76 which can be secured to the bottom rail 62 by screws 82 which are received in the spline 78. Unfortunately, the use of screws necessitates the use of a cover plate to hide the screws. Thus, the mechanism of securing the parts together dictates the appearance of the system.
U.S. Pat. No. 3,506,243 to Seiler discloses a rail which is formed of two extruded rail members 12 and 13. The Seiler systems require the use of different structures for the horizontal and vertical members.
In U.S. Pat. No. 3,770,245 to Murdock, an interlocking frame construction for supporting panels of wire mesh screen, or the like, is described which can be used as fencing along roadways. The posts are rectangular tubular members which can be formed by an extrusion process. The Murdock posts are of a heavy construction and provided with anchoring means for securing the posts into concrete. The grooves 33 in the posts 12 are wedge shaped to allow for firmly locking the side portions 37. The disclosed structure is designed for extreme rigidity as it can be used to protect pedestrians from falling off overpasses, etc. The design does not provide a desired level of versatility and the locking components 39 and 41 would suffer from the same problem noted in regard to U.S. Pat. No. 4,014,520, in that the locking pressure would be directly transmitted to the outer surface of the rail.
The anodized aluminum post of Trafton, U.S. Pat. No. 4,142,343 is of a circular configuration with "a plurality of longitudinal grooves in its outer periphery" to which to attach brackets. The post, although lightweight and maintenance free, would not provide for versatility of design.
U.S. Pat. No. 3,848,844, Barrett, discloses a post having vertical grooves along its length in each of its four sides, thus forming an X type configuration when viewed from the top. The grooves are used for the attachment of shelf support brackets.
U.S. Pat. No. 3,216,170, to Deadrick discloses the use of extruded metal to form desk legs. The extruded vertical support member 44, as illustrated in FIG. 5 of the Deadrick patent is provided with channels which can accommodate removable panels 45. The disclosure, however, does show that the physical structure must accommodate screws connections does not provide the versatility required to use the system for interchangeable use with furniture, rails, partitions and the like.
Rectangular cross sectional configuration posts are well known in the prior art patents, such as for rail systems. However, the prior art systems fail to provide the desired level of versatility without a sacrifice of aesthetic quality.